# A009355 (b-file synthesized from sequence entry)
0 0
1 1
2 -1
3 0
4 -4
5 40
6 -181
7 896
8 -8464
9 88320
10 -863041
11 9382912
12 -120330244
13 1676579840
14 -24638823301
15 390142722048
16 -6678730634944
17 121851014348800
18 -2353418855768161
19 48123147849826304
20 -1039698070255280164